feat: extract SeedControlButton component (#9744)

<img width="1048" height="482" alt="스크린샷 2026-03-12 오전 9 11 56"
src="https://github.com/user-attachments/assets/68009980-097c-4736-b7c4-eb8f9a6f05be"
/>

## Summary
- Extract inline value control button from `WidgetWithControl` into
reusable `SeedControlButton` component
- Support `badge` (pill) and `button` (square) variants per Figma design
system spec
- Use native `<button>` element for proper a11y (works with Reka UI's
`PopoverTrigger as-child`)

## Test plan
- [x] Verify seed control button renders correctly on KSampler node's
seed widget
- [x] Verify popover opens on click and mode selection works
- [x] Verify all 4 modes display correct icon/text (shuffle, pencil-off,
+1, -1)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9744-feat-extract-SeedControlButton-component-3206d73d365081a3823cc19e48d205c1)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: github-actions <github-actions@github.com>

knip.config.ts

@@ -11,7 +11,7 @@ const config: KnipConfig = {
         'src/types/index.ts',
         'src/storybook/mocks/**/*.ts'
       ],
-      project: ['**/*.{js,ts,vue}', '*.{js,ts,mts}']
+      project: ['**/*.{js,ts,vue}', '*.{js,ts,mts}', '!.claude/**']
     },
     'apps/desktop-ui': {
       entry: ['src/main.ts', 'src/i18n.ts'],